Anchor Sod Cherry beer, get on the 5 Pujonas Tokaj - it's a wine that tastes like nectar and oddly enough a great way to wash down a red hot Goulash. An alternative to the train is the boat - there's loads of them - gives you chance to stop off in Bratislava as well.
Vienna is ace - massive and majestic, the size being a throwback from the days of the inbreed Hapsburgs and their Austro-Hungarian empire. Get down the market - there's fabulous food and drink stalls. I don't know how busy it will be, but when we went as everything started to shut down at the start of the covid second wave, so there were hardly any tourists there - even Prague was quiet which was ace by me. Prague, we stayed in a hotel in the old town that had a bath with hot and cold water and a beer tap to use as much as you liked. We got a bollocking for not drinking enough.